High-pressure cold-water cleaning often does not have the desired effect. Usually, the specifications for impact are carefully pre-decided in terms of pressure and water volume but the cleaning result is not what was expected. Gavin Pote, Managing Director at Hawk Pumps, discusses the reasons it is important to identify whether hot or cold water washing will do the job, and shares a few potentially game-changing product solutions.
Cold Water Washing
- These machines tend to be less costly than hot water ones.
- They often use electric motors, where electric outlets are conveniently available.
- Hot water boilers require diesel for the burners and the use of this is not recommended in food processing or similar applications.
- Where the surface being cleaned is greasy and where cold water is necessary, a surfactant (detergent) has to be used prior to cleaning.
- Typically cold water is suitable for vehicle cleaning, roof cleaning, drain and sewer cleaning, removing concrete from steel and applications where the dirt does not have to be melted.
Hot Water Cleaning
- Cleaning with hot water tends to be more effective than cold water in a lot of cases.
- Hot water is indicated where the surfaces to be cleaned are greasy or waxy. Hot water tends to melt the dirt, allowing the water to emulsify it.
- Diesel powered hot water portable machines have no problem with burning diesel
- All-electric cabinet hot water machines are available for cleaning in those areas where burnt diesel fumes are not allowed. However 48Kw of electric elements are required to raise 15 l/min from ambient to 60ºC, and including the electric motor, the total draw is about 80 Amps.
- Boilers up to 500bar are available at present for volumes of 15-21 l/min
- Hot water stand alone boilers (“Hotboxes”) are popular for adding to existing cold water machines where hot water is needed only occasionally.
Hot water pressure washers are limited as off the shelf solutions and are usually available as cabinet mounted units or as an attachment, in the case of the HotBox.
Hawk’s Standard Range of Hot Water Equipment
We at Hawk recognize that customers have unique situations or a set of conditions that they need to operate under especially when it comes to hot water cleaning. As such, we are able to develop customized solutions to suit those customers’ unique circumstances.
Hawk’s Bespoke Hot Water Equipment
Large construction machines had to be serviced or repaired on site, often at night.
Hawk’s solution was to design a machine that had a pump, a boiler and a generator on a portable trolley. The generator has 2 power outlets which can be used for power tools and floodlights.
A company needed a diesel mobile unit that had to be able to provide hot water to clean the inside of large tankers that store palm oil.
Hawk’s solution was to incorporate our standard HotBox which is electrically operated (the burner is diesel-fired). We included a diesel generator to power the HotBox and provide additional source of power for tools, lights etc that may be needed on site.
A client required a hot water pressure washer to be fitted onto their truck. The unit would need to be run off the hydraulics of the vehicle.
It was needed to for cleaning of equipment on the mine which tends to be heavily incrusted in dirt and grime.
Hawk custom built a system mounted on a skid chassis which in turn was mounted to the truck and connected to the hydraulic system.
About Hawk
Hawk is a manufacturing company that primarily creates industrial high-pressure pumping and cleaning equipment. They also manufacture spraying solutions, including industrial nozzles. One of Hawk’s biggest strengths is that they have the capacity to manufacture, and custom design machines tailored to specific customer needs.
Hawk serves a wide range of customers from virtually every industrial sector, including processing plants, factories, workshops, contract cleaners, drain and sewer cleaners, car, truck and bus washers, mines, agricultural and more.

















